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Sun May 26, 2013 3:55 pm

Anyone ever built a 1915 with ported single port heads, stock 8 doweled crank, 34 pict with machined venturi, w100/w110 cam, standard 1 3/8 header with hideaway, and an 034 distributor for a daily street driver?

Just curious since I have all the parts to throw one together but just don't see a lot on the forum on this type of combination.

What do you guys think?

-Josh

Edit:
running ICT's
92mm thick walls

Sun May 26, 2013 4:08 pm

it will be wheezing anything above 4000 rpms depending on the porting on the heads. not enough air volume but that might be just me.

Sun May 26, 2013 4:19 pm

Thats what I would expect as well. Thats why I'm thinking of the cam choice being around the 100/110 spec. Seems like it would be a decent daily driver to work combo on the stop and go route. I was thinking a 1776 but its like $20 more to go 1915. Stock crank I wouldnt go above 4500 rpm on anyway so I would think the carb would act like a natural limiter to dangerous rpm's for a stock crank just like they had in mind from factory.

Sun May 26, 2013 4:23 pm

Is it a dual relief case? Do you already have it opened up for the 94 mm cylinders? People are practically giving away Single ICT's!

Sun May 26, 2013 4:27 pm

Yes, it is a dual relief case, not opened for 94mm yet. But getting ready to go to the machine shop.

Sun May 26, 2013 5:09 pm

Go for it! It could certainly do with a bit more carb than a single 34, but it will pull like a tram.

A pair of carbs and a touch up on the ports could make it a better driver.

Sun May 26, 2013 5:37 pm

I do have a pair of ict's but no single port manifolds. Dont know if I've ever even seen a pair of single port manifolds for ict's.

I do like the driveability of a 34 pict and an SVDA. I'd be happy trading the performance increase of duals for that reliability and driveability of the 34 pict. Plus the choke would be nice for the winters here. would the w100 run better with the 34 pict or should i just throw in the w110?

If anyone has any other opinions feel free to share

Sun May 26, 2013 6:06 pm

I also have a very very slightly used scat c35 that I could use also. Thats similar to the 110 correct?

Sun May 26, 2013 6:13 pm

you could always open up the single ports for biger valves and open up for a lot biger intake size then add a devider so it isant a single port but looks like it.

Sun May 26, 2013 6:22 pm

mark tucker wrote: you could always open up the single ports for bigger valves and open up for a lot bigger intake size then add a devider so it isn't a single port but looks like it.

I sense some sarcasm :P

Sun May 26, 2013 6:22 pm

With a 34 PICT there is no point in going over a 1776. Even if it only $20 more you will not be getting your moneys worth out of a 1915. A W-110 cam is too big for any engine with a stock 34 PICT carb. Use the stock cam or a CB cheater cam.

Sun May 26, 2013 6:23 pm

the engle 100 is ok, or stay under 240 degrees @ .050 duration. I have seen similar engines built, and honestly even the engle 120 cam runs better than you'd expect(not good mind you, but it not bad either), but the more cam the more uneven the VE is between front and back cylinders (charge robbing)!

the 30 pict is so small that I think it is silly to use any more than the stock cam, the 34 pict is a better size if you can get one that works well.

Sun May 26, 2013 6:23 pm

I think a special grind that is 110 intake and 100 exhaust on the usual 108 lobe centers would be good. Otherwise use the w100 and add 1.25 rockers to the intakes only.

I have thought of building this exact engine. It will need a fair amount of port work to work well, but nothing radical I think.

The others seemed to miss your mention of 34 pict with enlarged Venturi. Alstrup has pulled some impressive numbers with modified 34 pict carbs.

Sun May 26, 2013 6:32 pm

modok wrote: the engle 100 is ok, or stay under 240 degrees @ .050 duration. I have seen similar engines built, and honestly even the engle 120 cam runs better than you'd expect(not good mind you, but it not bad either), but the more cam the more uneven the VE is between front and back cylinders (charge robbing)!

the 30 pict is so small that I think it is silly to use any more than the stock cam, the 34 pict is a better size if you can get one that works well.

I do plan on running a 34 pict with a modified venturi to 28mm-30mm

Sun May 26, 2013 6:33 pm

You said "34 pict with machined venturi"...What does that mean as I have not heard the term before. I am interested in the machining.
I have always wished for a 35 or 36 solex single center mount carb.
Yes you may have a decent balance of power simplicity and economy.

Sun May 26, 2013 6:38 pm

The venturi on the 34 pict is removable, you can take it off and bore it out from its stock 26mm to 28mm to 30mm etc. You can also get them to work by removing the venturi but I dont plan on fussing with that. You can easily bore the venturi to 28-30mm and rejet for larger applications. There are a few videos about it on youtube that explain in more detail and you can also find some resources about the modification on this forum as well. A guy runs a 1904cc with the modified 34 pict in the video on youtube.

Sun May 26, 2013 7:52 pm

I tried that combination of a larger drilled out venturi and a W-110 Cam, in a otherwise stock 1600 Dual Port "Blah"!. I would go with the W-100 cam unless your going to run twin carbs and jack up the compression. The W-100 works great with the single port manifold which is about 32 mm in size. That is the combination I put a single old 32 mm PBIC solex Porsche 356 carb on and when I plugged the air correction jet the engine really woke up. But I wound up running a stock VW Solex 28 mm PICT carb because the milage went way up with it. The engine did not have any trouble making 4400 RPM but that was with 85.5 Piston and Cylinders.
I think the single port manifold is going to limit you to a 32 mm or smaller carburetor. I would think the engine would breath like a dragon with the W-100 camshaft but with the 94 mm cylinders it's not going to rap up very high in RPM.

Sun May 26, 2013 7:53 pm

My buddy Jerry out in CA did a 1915 single port for his Beetle once, you couldn't really tell it was anything more than a stocker it just had a little more torque.

Sun May 26, 2013 8:44 pm

Interesting. Well thats somewhat disappointing.

Sun May 26, 2013 9:00 pm

my 1904 singlport is approx 30% more powerful than any stock 1600, but it wasn't just "thrown together" either